Bug in RollingFileAppender.cs causing failure to timely roll files on monthly interval

• Key: LOG4NET-60
• Type: Bug
• Status: Resolved
• Resolution: Fixed
• Priority: Major
• Assignee: Nicko Cadell
• Reporter: Lanchon
• Component/s: Appenders
• Affects Version/s: 1.2.9
• Fix Version/s: 1.2.10

Description

code in said file looks like this

case RollPoint.TopOfMonth:
current = current.AddMilliseconds(-current.Millisecond);
current = current.AddSeconds(-current.Second);
current = current.AddMinutes(-current.Minute);
current = current.AddHours(-current.Hour);
current = current.AddMonths(1);
break;

i belive it should look something like this

case RollPoint.TopOfMonth:
current = current.AddMilliseconds(-current.Millisecond);
current = current.AddSeconds(-current.Second);
current = current.AddMinutes(-current.Minute);
current = current.AddHours(-current.Hour);
current = current.AddDays(1 - current.Day); // this line seems to be needed
current = current.AddMonths(1);
break;



also in a separate issue, since there is no RollPoint.TopOfYear, this comment in another part of the code seems wrong:

//is the new file name equivalent to the 'current' one
//something has gone wrong if we hit this -- we should only
//roll over if the new file will be different from the old
string dateFormat = m_now.ToString(m_datePattern, System.Globalization.DateTimeFormatInfo.InvariantInfo);
if (m_scheduledFilename.Equals(File + dateFormat))
{
ErrorHandler.Error("Compare " + m_scheduledFilename + " : " + File + dateFormat);
return;
}

if the date pattern specifies only the year (rolling yearly), then i think this "error" will be triggered incorrectly 11 times a year. it's fine not to roll, but reporting an error is inappropriate.

Comments

[Nicko Cadell]

The first point about the missing AddDays(1 - current.Day) is valid and I will check in a fix for this.

The second point I don't think is valid because there is not TopOfYear roll point. On its own the year cannot be used as a date pattern. When the date pattern is set to 'yyyy' the appender does not fall back to TopOfMonth but rather generates the following error message in the log4net internal debug log:

log4net:ERROR XmlHierarchyConfigurator: Could not create Appender [RollingFileAppender] of type [log4net.Appender.RollingFileAppender]. Reported error follows.
System.ArgumentException: Invalid RollPoint, unable to parse [yyyy]
   at log4net.Appender.RollingFileAppender.ActivateOptions() in C:\work\svn_root\apache\log4net\trunk\src\Appender\RollingFileAppender.cs:line 960

The appender is not configured or attached to any loggers, therefore the suggested error message would not occur.

[Nicko Cadell]

Checked in a fix for the incorrect calculation of the NextCheckDate for the TopOfMonth roll point.